The Internet book: everything you need to know about computer networking and how the Internet works

405 Pages·2019·5.46 MB·English

by  Comer

The Internet Book
Everything You Need to Know
about Computer Networking
and How the Internet Works
Fifth Edition
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The Internet Book
Everything You Need to Know
about Computer Networking
and How the Internet Works
Fifth Edition
Douglas E. Comer
Departments of Computer Science and ECE
Purdue University
West Lafayette, IN
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CRC Press
Taylor & Francis Group
6000 Broken Sound Parkway NW, Suite 300
Boca Raton, FL 33487-2742
© 2019 by Taylor & Francis Group, LLC
CRC Press is an imprint of Taylor & Francis Group, an Informa business
No claim to original U.S. Government works
Printed on acid-free paper
Version Date: 20180730
International Standard Book Number-13: 978-1-138-33133-4 (Hardback)
International Standard Book Number-13: 978-1-138-33029-0 (Paperback)
This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been
made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity
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Library of Congress Cataloging-in-Publication Data
Names: Comer, Douglas, author.
Title: The Internet book : everything you need to know about computer
networking and how the Internet works / Douglas E. Comer.
Description: Fifth edition. | Boca Raton : Taylor & Francis, CRC Press, 2018.
| Includes bibliographical references and index.
Identifiers: LCCN 2018021320 | ISBN 9781138330290
Subjects: LCSH: Internet. | Computer networks. | World Wide Web.
Classification: LCC TK5105.875.I57 C65 2018 | DDC 004.67/8--dc23
LC record available at https://lccn.loc.gov/2018021320
Visit the Taylor & Francis Web site at
http://www.taylorandfrancis.com
and the CRC Press Web site at
http://www.crcpress.com
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 Copyright 2018 All rights reserved.
This document may not be reproduced by any means
without the express written consent of the author.
 Copyright 2018 All rights reserved.
This document may not be reproduced by any means
without the express written consent of the author.
To EveryoneWho
Is Curious
To EveryoneWho
Is Curious
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Contents
Preface xxiii
Chapter 1 The Internet Is Everywhere 3
1.1 Basic Facts Do Not Tell The Story 5
1.2 Imagine Life Without The Internet 5
1.3 Why You Should Understand Internet Technology 6
1.4 Learning About The Internet 6
1.5 Understanding The Big Picture 7
1.6 Terminology And Technology 7
1.7 Growth And Adaptability 8
1.8 The Impact Of The Internet 8
1.9 Organization Of The Book 8
1.10 A Personal Note 9
PART I Before The Internet 11
Chapter 2 Telephones Everywhere 15
2.1 Introduction 15
2.2 A Communication Service 15
2.3 Selling Communication 15
2.4 Limited Access 16
2.5 High Cost 17
2.6 The Difficult Transition 17
2.7 Ubiquitous Access 18
2.8 RelevanceTo The Internet 19
2.9 Summary 19
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Contents
Contents
Preface xxiii
Preface xxiii
Chapter 1 The Internet Is Everywhere 3
C1.h1aptBears1ic FTahcetsIDntoeNrnoettTIesllETvheerSytworhye r e5 3
1.2 Imagine Life Without The Internet 5
1.31.1 WhByasYiocuFSahcotsulDdoUNnodterTsetlalnTdhIentSetronreyt T e5chnology 6
1.41.2 LeIamrnaignigneALbiofuetWTihtehoIuntteTrhneetI n te6rnet 5
1.51.3 UnWdehrystYaonudiSnhgoTulhdeUBnigdePriscttaunrde I n t7ernet Technology 6
1.61.4 TeLrmeainrnoilnoggyAAbonudtTTehcehnInotleorgnye t 7 6
1.71.5 GrUowndtherAstnadndAidnagpTtahbeilBitiyg P i8cture 7
1.81.6 ThTeeIrmmpinaocltoOgyf TAhnedITnetecrhnneot l o g8y 7
1.91.7 OrGgaronwiztahtiAonndOAfdTahpetaBboiloikty 88
1.110.8 A PTheresIomnaplacNtoOtef T h9e Internet 8
1.9 Organization Of The Book 8
1.10 A Personal Note 9
PART I Before The Internet 11
PART I Before The Internet 11
Chapter 2 Telephones Everywhere 15
C2.h1aptIenrtr2oduTcetiloenp h o1n5es Everywhere 15
2.2 A Communication Service 15
2.32.1 SeIllnitnrgodCuocmtiomnu n ic1a5tion 15
2.42.2 LimAiCteodmAmccuensisc a t io1n6Service 15
2.52.3 HiSgehllCinogstC o m17munication 15
2.62.4 ThLeimDiitfefidcuAltccTersasn s it1io6n 17
2.72.5 UbHiqiguhitoCuossAt c ce1s7s 18
2.82.6 ReTlehveaDncieffiTcoulTthTeraInnsteitrinoent 1179
2.92.7 SuUmbmiqauryit o u 1s9Access 18
2.8 RelevanceTo The Internet 19
2.9 Summary 19
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viii Contents Contents ix
Chapter 3 The World Was Once Analog 23 5.7 A Character Code For Digital Information 48
5.8 Bits And Bytes 50
3.1 Introduction 23 5.9 Detecting Errors 50
3.2 Sound, Vibrations, And Analog Recording 23 5.10 Summary 51
3.3 Analog Electronic Devices 24
3.4 Many Electronic DevicesAre Analog 25
3.5 The First Analog Communication 25 Chapter 6 Local Area Networks 55
3.6 Sending An Analog Signal Across A Wire 26
3.7 Analog Is Simple But Inaccurate 27 6.1 Introduction 55
3.8 A Definition Of Digital 27 6.2 The Digital Revolution 55
3.9 Digital Music 28 6.3 The Move To Multiple Computers 56
3.10 Recording Sound As Numbers 28 6.4 Removable Media And Manual Transfer 56
3.11 Converting Between Analog And Digital Forms 31 6.5 Early Computers Used Circuit Boards 57
3.12 Why Did Digital Music Take Over? 32 6.6 LANs 58
3.13 Summary 33 6.7 The LAN Approach 58
6.8 LAN Hardware 59
6.9 Wireless LAN (WLAN) Connections 60
Chapter 4 The Past And Present Digital Network 37 6.10 Wired And Wireless LAN Technologies 60
6.11 Wireless PAN Technology 61
4.1 Introduction 37 6.12 Connecting A DeviceTo An Ethernet 61
4.2 The World Was Previously Digital 37 6.13 Connecting A DeviceTo A Wi-Fi Network 62
4.3 A Telegraph Was Digital 38 6.14 Wi-Fi Security 63
4.4 Morse Code 38 6.15 The Importance Of LAN Technology 63
4.5 Letters And Digits In Morse Code 39 6.16 Relationship To The Internet 64
4.6 Telegraph Users Did Not Encounter Morse Code 40
4.7 Virtually Instant Communication 40
4.8 Speed Is Relative 40 PART II A Brief History Of The Internet 65
4.9 The Telephone Eventually BecameDigital 41
4.10 RelevanceTo The Internet 41
4.11 Binary Encoding Of Data On The Internet 42 Chapter 7 Internet: Motivation And Beginnings 69
4.12 Why Use Two Symbols? 42
4.13 Summary 42 7.1 A Proliferation Of LANs 69
7.2 No Technology Solves All Problems 70
7.3 Wide Area Network Technologies 70
Chapter 5 Basic Communication 45 7.4 Can We Build A Global WAN? 71
7.5 U.S. Department Of Defense Networking Research 72
5.1 Introduction 45 7.6 Experimental Research 72
5.2 Communication Using Electricity 45 7.7 The Internet Emerges 72
5.3 Sending Signals 46 7.8 The ARPANET Backbone 73
5.4 Using Signals To Send Information 46 7.9 Internet Software 73
5.5 Modem: A Modulator And A Demodulator Combined 47 7.10 The Name Is TCP/IP 74
5.6 How Modems Allow Two-Way Traffic 48 7.11 The Surprising Choice Of Open Standards 74
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viiiviii ConCtoennttsents ConCtoennttsen t s ix ix
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